The study will consent 30 patients undergoing surgery through the abdominal wall and the skin incision will intentionally be left open. Subjects will be randomized using a random number generator. Each number will be placed in an envelope numbered 1-30. Arm 1 will be even numbers and Arm 2 will be odd numbers. A researcher not affiliated with the study will generate the numbers and place them in the envelopes. Arm 1 will place fifteen subjects on Negative Pressure Therapy Only and Arm 2 will place fifteen subjects on Negative Pressure and Procellera. Arm 1 (Negative Pressure Only) will have their dressing changed 3 times per week which is the standard of care for Negative Pressure Therapy. Arm 2 (Negative Pressure Therapy and Procellera) will have their dressing changed every 5 days. Arm 1 and 2 will have a tissue specimen taken on the 5th day only. The tissue will be taken from debrided material and sent for culture. The Negative Pressure Therapy Sponge, which is discarded after each dressing change, will be collected, lavaged with saline and the cells will be examined for macrophage function and the wound fluid will be tested for inflammation response. Photographs, wound measurements, pain scale and pain medication will also be completed at each dressing change. We will check the progress of the wound along with your surgeon during the subject's 30 day surgical follow up in the surgeon's office. The wound will be measured (if not healed), photograph's taken and their pain level assessed.